Plastic mug



FIG. 1 is a first perspective view of a plastic mug showing my new design;

FIG. 2 is a second perspective view thereof;

FIG. 3 is a third perspective view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a side view thereof; and,

FIG. 7 is a front view thereof (the rear view being a mirror image thereof).

The broken lines in the drawings depict portions of the plastic mug that form no part of the claimed design. 

CLAIM The ornamental design for a plastic mug, as shown and described. 